f2fs: check in-memory sit version bitmap
This patch adds a mirror for sit version bitmap, and use it to detect
in-memory bitmap corruption which may be caused by bit-transition of
cache or memory overflow.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 56a097d..c8c8255 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -2346,7 +2346,7 @@ static int build_sit_info(struct f2fs_sb_info *sbi)
struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
struct sit_info *sit_i;
unsigned int sit_segs, start;
- char *src_bitmap, *dst_bitmap;
+ char *src_bitmap;
unsigned int bitmap_size;
/* allocate memory for SIT information */
@@ -2408,17 +2408,22 @@ static int build_sit_info(struct f2fs_sb_info *sbi)
bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
- dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
- if (!dst_bitmap)
+ sit_i->sit_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
+ if (!sit_i->sit_bitmap)
return -ENOMEM;
+#ifdef CONFIG_F2FS_CHECK_FS
+ sit_i->sit_bitmap_mir = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
+ if (!sit_i->sit_bitmap_mir)
+ return -ENOMEM;
+#endif
+
/* init SIT information */
sit_i->s_ops = &default_salloc_ops;
sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
sit_i->written_valid_blocks = 0;
- sit_i->sit_bitmap = dst_bitmap;
sit_i->bitmap_size = bitmap_size;
sit_i->dirty_sentries = 0;
sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
@@ -2826,6 +2831,9 @@ static void destroy_sit_info(struct f2fs_sb_info *sbi)
SM_I(sbi)->sit_info = NULL;
kfree(sit_i->sit_bitmap);
+#ifdef CONFIG_F2FS_CHECK_FS
+ kfree(sit_i->sit_bitmap_mir);
+#endif
kfree(sit_i);
}
diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
index 9af9519..5cb5755 100644
--- a/fs/f2fs/segment.h
+++ b/fs/f2fs/segment.h
@@ -209,6 +209,9 @@ struct sit_info {
block_t sit_blocks; /* # of blocks used by SIT area */
block_t written_valid_blocks; /* # of valid blocks in main area */
char *sit_bitmap; /* SIT bitmap pointer */
+#ifdef CONFIG_F2FS_CHECK_FS
+ char *sit_bitmap_mir; /* SIT bitmap mirror */
+#endif
unsigned int bitmap_size; /* SIT bitmap size */
unsigned long *tmp_map; /* bitmap for temporal use */
@@ -423,6 +426,12 @@ static inline void get_sit_bitmap(struct f2fs_sb_info *sbi,
void *dst_addr)
{
struct sit_info *sit_i = SIT_I(sbi);
+
+#ifdef CONFIG_F2FS_CHECK_FS
+ if (memcmp(sit_i->sit_bitmap, sit_i->sit_bitmap_mir,
+ sit_i->bitmap_size))
+ f2fs_bug_on(sbi, 1);
+#endif
memcpy(dst_addr, sit_i->sit_bitmap, sit_i->bitmap_size);
}
@@ -643,6 +652,12 @@ static inline pgoff_t current_sit_addr(struct f2fs_sb_info *sbi,
check_seg_range(sbi, start);
+#ifdef CONFIG_F2FS_CHECK_FS
+ if (f2fs_test_bit(offset, sit_i->sit_bitmap) !=
+ f2fs_test_bit(offset, sit_i->sit_bitmap_mir))
+ f2fs_bug_on(sbi, 1);
+#endif
+
/* calculate sit block address */
if (f2fs_test_bit(offset, sit_i->sit_bitmap))
blk_addr += sit_i->sit_blocks;
@@ -668,6 +683,9 @@ static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start)
unsigned int block_off = SIT_BLOCK_OFFSET(start);
f2fs_change_bit(block_off, sit_i->sit_bitmap);
+#ifdef CONFIG_F2FS_CHECK_FS
+ f2fs_change_bit(block_off, sit_i->sit_bitmap_mir);
+#endif
}
static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi)